An array of patients can benefit from receiving therapeutic gas (e.g., nitric oxide gas) in inspiratory breathing gas flow. The therapeutic gas can be delivered, for example, from a breathing circuit affiliated with a ventilator (e.g., constant flow ventilator, variable flow ventilator, high frequency ventilator, bi-level positive airway pressure ventilator or BiPAP ventilator, etc.). In operation, therapeutic gas may be injected into the inspiratory breathing gas flowing in the breathing circuit of the ventilator device. This inhaled therapeutic gas is often provided via a therapeutic gas delivery system at a constant concentration, which is provided based on proportional delivery of the therapeutic gas to the breathing gas. Further, a sampling system (e.g., affiliated the therapeutic gas delivery system) may continuously draw in the inspiratory breathing gas flow to at least confirm that the desired dose of the therapeutic gas in the inspiratory breathing gas flow is being delivered to the patient. Example operation can include a sample pump pulling in inspiratory flow (e.g., in the near vicinity of the patient) to confirm that the desired therapeutic gas concentration is in fact being delivered to the patient.
One such therapeutic gas is inhaled nitric oxide (iNO), which can be used as a therapeutic gas to produce vasodilatory effect on patients. When inhaled, iNO acts to dilate blood vessels in the lungs, improving oxygenation of the blood and, for example, reducing pulmonary hypertension. Accordingly, nitric oxide is provided in inspiratory breathing gases for patients with various pulmonary pathologies including, but not limited to, hypoxic respiratory failure (HRF) and persistent pulmonary hypertension (PPH). The actual administration of iNO is generally carried out by introduction into the patient as a gas along with other normal inhalation gases. For example, iNO can be introduced, from an iNO delivery system, into the inspiratory flow of a patient breathing circuit affiliated with a ventilator.
Separately and/or in conjunction with iNO, patients may receive inspiratory breathing gas flow containing liquid particles (e.g., nebulized medical solutions and suspensions, moisture from humidified air, etc.) and/or other particles. However, as described above, iNO delivery systems may include a sampling system to confirm dosing of iNO being delivered to the patient. Liquid particles in the inspiratory breathing flow, even though they may provide additional benefit to the patient, may contaminate the sampling system (e.g., gas analyzers). Accordingly, at times, there is a need to filter the sampled inspiratory breathing gas flow of liquid particles and/or other particles, for purposes such as mitigating contamination of the gas sampling system.
Associated with filtering liquid particles from the inspiratory breathing flow, there is a need to trap the liquid particles that are removed. Various configurations of such traps, and various techniques directed to detecting the fluid level in the traps, are known. Additional desired features of the level detection may include tolerance for various orientations of the trap, ability to detect proper installation of the trap, simplicity, and ready adaptability to different capacities of traps. Accordingly, there is a need for an improved apparatus and method to trap, and detect accumulated levels of liquid particles filtered from inspiratory breathing gas flow being provided to a patient in need thereof.